Films of high Tc oxide superconductors.

摘要

Superconducting transition metal oxide films are provided which exhibit very high onsets of superconductivity and superconductivity at temperatures in excess of 40K. These films are produced by vapour deposition processes using pure metal sources for the metals in the superconducting composition, where the metals include multi-valent nonmagnetic transition metals, rare earth elements, and/or rare earth-like alkaline earth elements. The substrate is exposed to oxygen during vapour deposition and, offer formation of the film, ambient followed by at least one annealing step in an oxygen ambient and slow cooling over several hours to room temperature. The substrates chosen are not critical as long as they are not adversely reactive with the superconducting oxide film. Transition metals include Cu, Ni, Ti, and V, while the rare earth-like elements include Y, Ca, Ba, and Sr.